» Family Baetidae (Blue-Winged Olives)
11 genera (Americabaetis, Baetodes, Baetopus, Barbaetis, Camelobaetidius, Cloeodes, Moribaetis, Paracloeodes, Pseudocentroptiloides, Varipes, Waynokiops)
aren't included.
Common Name
This is page 3 of specimens of Baetidae. Visit the main Baetidae page for:
- The behavior and habitat of Baetidae.
- 10 underwater pictures of Baetidae.
Pictures of 103 Mayfly Specimens in the Family Baetidae:
Baetidae (Blue-Winged Olives) Mayfly Nymph
View 5 PicturesThis nymph has only two real tails. The third is present, but too short to see in these pictures. It has particularly small gills and indistinct gill veinlets (Veinlet: Short insect wing veins connecting the major longitudinal veins to the wing margin.). Male Acentrella turbida (Tiny Blue-Winged Olive) Mayfly Spinner
View 3 PicturesI would not like to have to match this hatch. These are the smallest mayflies I have ever seen. I used to think Caenis was the smallest adult mayfly in the west but these guys are about 4mm long. The male eyes are two toned, brown above and olive below. The abdomen is dark brown interspersed with light brown. The abdomen is clear for the anterior (Anterior: Toward the front of an organism's body. The phrase "anterior to" means "in front of.") 2/3rd and the remainder is white. The tails are twice as long as the insect. There is only one pair of wings. Baetidae (Blue-Winged Olives) Mayfly Nymph
View 4 PicturesThis Baetis nymph is quite a bit larger than any of the others I found in winter 2004. Abdomen segment 5 is only slightly pale while 9 and 10 are quite pale. The tail is banded at the tip. Its body measures about 9mm long. It's much larger than the other Baetis specimens I collected, and it has quite well-developed wingpads.
It's most likely a mature nymph from a very early-hatching brood. It comes from the headwaters of a very small, very spring-fed Lake Superior tributary, which wasn't at all frozen despite very frigid temperatures and 3 feet of snow on the ground.